Mobility Spectrum Techniques for Determination of Multi-Carrier Transport Parameters in Advanced Nanoelectronic Structures
Abstract: For modern semiconductor multi-layer device structures containing multiple populations of distinct carrier species, conventional Hall and resistivity data acquired at a single magnetic field provide far less information than measurements as a function of magnetic field. However, the extraction of reliable and accurate individual carrier densities and corresponding mobilities from the field-dependent data can present a number of difficult challenges, which were never fully overcome by methods such as multi-carrier fitting, the mobility spectrum analysis of Beck and Anderson, or hybrid mixed-conduction analysis. More recently, in order to overcome the limitations of these methods, several research groups have contributed to development of the quantitative mobility spectrum analysis (QMSA) procedure, which is now available as a commercial product. The algorithm is analogous to a fast Fourier transform, in that it transforms data from the magnetic field domain to the mobility domain. QMSA converts the field-dependent Hall and resistivity data into visually-meaningful transformed outputs comprising the conductivity density of electrons and holes in the mobility domain. In this talk, the development of QMSA will be presented, as well as practical examples of the application of QMSA to synthetic data sets and real experimental data that are representative of modern semiconductor nanoelectronic device structures. In addition, a new High Resolution MSA (HR-MSA) procedure will be introduced, which is more robust than previous algorithms, and which has the unique capability of accurately resolving fine detail in the distribution of carrier mobilities. Some recent examples will be presented on the application of HR-MSA to AlGaN/GaN HEMT structures, nano-scale SOI structures, multi-layer compound semiconductor nanostructures, and to vertical minority carrier transport in InAs/GaSb Type-II Superlattices.
